What does the SRM slope represent?
The slope is the relationship of torque to frequency of the crank. (i.e. when you apply torque to the crank, a corresponding frequency will be sent to the PowerControl) Because the relationship is directly proportional it is represented as a constant, meaning that it remains the same no matter what torque is applied. That is why the one number can be used to calculate power at any given torque. You can see from the graph the importance of setting the zero offset frequency correctly — if it is too high or too low the rest of the power calculation will be incorrect. If the slope and the zero offset frequency are correct, the measurement of power will be very precise, as low as +/-1% error.
